Who has experience with this and is willing to help? What is mssing? What is an easy way to contribute?
There is also a specific Photo CD Preservation project.
Retrostuff:"To get started with Redump, you need to know that it is a database only; there are no disc images hosted on their servers [1]. If you want to help by submitting data to the database, you should check if your hardware/system meets the requirements [2] first. There is a command line tool available for dumping [2] and also a new GUI for the tool [3]. Regarding CD-i: It is very simple to dump these discs, as long as they are standard Green Book discs. Some will give you trouble though and generate errors. When it comes to CD-i Ready and CD-i Bridge discs, these will definitely give you trouble and might need manual rework, if they can be dumped at all."
[1] http://wiki.redump.org/index.php?title=Redump.org
[2] http://wiki.redump.org/index.php?title=CD_Dumping_Guide_(DIC_CLI)
[3] http://wiki.redump.org/index.php?title=Disc_Dumping_Guide_(DICUI)
[Thanks, Dizzzy Dubs, Retrostuff]